Algo VPN – Set up a personal IPSEC VPN in the cloud

Algo VPN is a set of Ansible scripts that simplify the setup of a personal IPSEC VPN. It uses the most secure defaults available, works with common cloud providers, and does not require client software on most devices.

Download Algo. Unzip it in a convenient location on your local machine.

Install Algo’s core dependencies. Open the Terminal. The python interpreter you use to deploy Algo must be python2. If you don’t know what this means, you’re probably fine. cd into the algo-master directory where you unzipped Algo, then run:

On macOS, you may be prompted to install cc. You should press accept if so.

List the users to create. Open config.cfg in your favorite text editor. Specify the users you wish to create in the users list.

Start the deployment. Return to your terminal. In the Algo directory, run ./algo and follow the instructions. There are several optional features available. None are required for a fully functional VPN server. These optional features are described in greater detail in deploy-from-ansible.md.

That’s it! You will get the message below when the server deployment process completes. You now have an Algo server on the internet. Take note of the p12 (user certificate) password in case you need it later.
You can now setup clients to connect it, e.g. your iPhone or laptop. Proceed to Configure the VPN Clients below.

Configure the VPN Clients
Certificates and configuration files that users will need are placed in the configs directory. Make sure to secure these files since many contain private keys. All files are saved under a subdirectory named with the IP address of your new Algo VPN server.

Apple DevicesSend users their Apple Profile. Find the corresponding mobileconfig (Apple Profile) for each user and send it to them over AirDrop or other secure means. Apple Configuration Profiles are all-in-one configuration files for iOS and macOS devices. On macOS, double-clicking a profile to install it will fully configure the VPN. On iOS, users are prompted to install the profile as soon as the AirDrop is accepted.Turn on the VPN. On iOS, connect to the VPN by opening Settings and clicking the toggle next to “VPN” near the top of the list. On macOS, connect to the VPN by opening System Preferences -> Network, finding Algo VPN in the left column and clicking “Connect.” On macOS, check “Show VPN status in menu bar” to easily connect and disconnect from the menu bar.Managing On-Demand VPNs. If you enabled “On Demand”, the VPN will connect automatically whenever it is able. On iOS, you can turn off “On Demand” by clicking the (i) next to the entry for Algo VPN and toggling off “Connect On Demand.” On macOS, you can turn off “On Demand” by opening the Network Preferences, finding Algo VPN in the left column, and unchecking the box for “Connect on demand.”

Android Devices
No version of Android supports IKEv2. Install the strongSwan VPN Client for Android 4 and newer. Import the corresponding user.p12 certificate to your device. See the Android setup instructions for more a more detailed walkthrough.

Windows 10
Copy your PowerShell script windows_{username}.ps1 and p12 certificate {username}.p12 to the Windows client and run the following command as Administrator to configure the VPN connection.

Linux Network Manager Clients (e.g., Ubuntu, Debian, or Fedora Desktop)
Network Manager does not support AES-GCM. In order to support Linux Desktop clients, choose the “compatible” cryptography during the deploy process and use at least Network Manager 1.4.1. See Issue #263 for more information.

Linux strongSwan Clients (e.g., OpenWRT, Ubuntu Server, etc.)
Install strongSwan, then copy the included ipsec_user.conf, ipsec_user.secrets, user.crt (user certificate), and user.key (private key) files to your client device. These will require customization based on your exact use case. These files were originally generated with a point-to-point OpenWRT-based VPN in mind.

Other Devices
Depending on the platform, you may need one or multiple of the following files.

cacert.pem: CA Certificate

user.mobileconfig: Apple Profile

user.p12: User Certificate and Private Key (in PKCS#12 format)

user.sswan: Android strongSwan Profile

ipsec_user.conf: strongSwan client configuration

ipsec_user.secrets: strongSwan client configuration

windows_user.ps1: Powershell script to help setup a VPN connection on Windows

Setup an SSH Tunnel
If you turned on the optional SSH tunneling role, then local user accounts will be created for each user in config.cfg and SSH authorized_key files for them will be in the configs directory (user.ssh.pem). SSH user accounts do not have shell access, cannot authenticate with a password, and only have limited tunneling options (e.g., ssh -N is required). This ensures that SSH users have the least access required to setup a tunnel and can perform no other actions on the Algo server.
Use the example command below to start an SSH tunnel by replacing user and ip with your own. Once the tunnel is setup, you can configure a browser or other application to use 127.0.0.1:1080 as a SOCKS proxy to route traffic through the Algo server.ssh -D 127.0.0.1:1080 -f -q -C -N user@ip -i configs/ip_user.ssh.pem

SSH into Algo Server
To SSH into the Algo server for administrative purposes you can use the example command below by replacing ip with your own:ssh root@ip -i ~/.ssh/algo.pem
If you find yourself regularly logging into Algo then it will be useful to load your Algo ssh key automatically. Add the following snippet to the bottom of ~/.bash_profile to add it to your shell environment permanently.ssh-add ~/.ssh/algo > /dev/null 2>&1
Note the admin username is ubuntu instead of root on providers other than Digital Ocean.

Adding or Removing Users
If you chose the save the CA certificate during the deploy process, then Algo’s own scripts can easily add and remove users from the VPN server.

Update the users list in your config.cfg

Open a terminal, cd to the algo directory, and activate the virtual environment with source env/bin/activate

Run the command: ./algo update-users

After this process completes, the Algo VPN server will contains only the users listed in the config.cfg file.